1. Field of the Invention
Emergency preservation and resuscitation methods are provided, along with kits for implementing those methods in the field.
2. Description of the Related Art
Emergency preservation and resuscitation is, without limitation, the therapeutic induction of a state of tolerance to temporary, complete systemic ischemia (deficiency of blood supply). Emergency preservation and resuscitation is an interventional preservation measure for patients/victims who cannot be immediately resuscitated, for example and without limitation, in pre-hospital, hospital and field scenarios. These patients may be prevented from dying by inducing such preservative measures until evacuated to a medical center for emergency medical/surgical intervention and delayed resuscitation can be completed. These victims would otherwise die at the point-of-injury or in the field because definitive medical/surgical procedures are not immediately available and/or could not be brought to the point-of-injury. The potential emergency medical market sector for use is very large. Approximately 1,200-1,500 victims each day in the United States alone die from sudden cardiac arrest that cannot be reversed or recovered in the field through defibrillation or other currently available advanced cardiopulmonary cerebral resuscitation techniques. Trauma victim deaths add another 250 cases per day in the United States that may benefit from life-saving emergency preservation and resuscitation procedures. This number due to trauma could be substantially greater during warfare or terrorist attack. These trauma and sudden cardiac arrest victims could potentially be protected by deep, profound or ultra-profound hypothermia, as may be necessary, enabling evacuation to a medical center followed by more sophisticated, hospital-based, life-saving interventions. However, current methods for reproducibly preserving life during a cardiopulmonary arrest of more than one-to-two hours in duration are not available.
U.S. Pat. No. 5,149,321 to Klatz et al. (the '321 patent) discloses a method and devices purportedly useful in resuscitating the brain of a patient suffering from ischemic and anoxic injury using oxygenated fluids. The fluids are introduced into one or both of the external carotid arteries. The fluid is oxygenated and contains: barbiturates; oxygen carrying agents; antioxidants; Lazeroids; carrier vehicles, preferably dimethyl sulfoxide (DMSO) and, optionally, physiological buffers; nutrients, such as glucose; and “other chemicals,” such as an anticoagulant). The fluid is delivered at approximately 40° F. (4.44° C.). An integrated device, including a reservoir, oxygenator, pump and logic control unit, useful in delivering the fluid to a patient is disclosed in the '321 patent. The '321 patent does not disclose or suggest use of saline-based aqueous solutions, does not address the need to reach any target brain (tympanic) temperature, does not disclose whole-body flushing, does not provide any details on how to resuscitate the patient, and, importantly, does not indicate that they can achieve successful resuscitation using those methods.
U.S. Pat. No. 5,827,222 to Klatz et al. is a member of a chain of Continuations-In-Part of a Divisional of the '321 patent. It further describes organ preservation techniques that involve flushing a patient's circulatory system and/or body cavities with a chilled organ preservation solution. The organ preservation solution, as with the brain preservation solution described in the '321 patent, is preferably a DMSO-based solution, with no disclosure of the usefulness of a saline-based solution. This reference does not disclose or suggest use of saline-based aqueous solutions, does not address the need to reach any target brain (tympanic) temperature, does not provide any details on how to resuscitate the patient, and, importantly, does not indicate that they can achieve successful resuscitation using those methods.
U.S. Pat. No. 6,485,450 to Owen discloses an integrated device useful in delivering fluids, as in the methods described in the '321 patent. The fluid is described as a “medical fluid,” which may be blood or crystalloid solution. As above, no resuscitation techniques are mentioned and no success in resuscitation is discussed.
In Behringer et al. (Behringer W, Safar P, Wu X, Kentner R, Radovsky A, Kochanek P M, Dixon C E, Tisherman S A, “Survival without brain damage after clinical death of 60-120 min in dogs using suspended animation by profound hypothermia,” Crit Care Med 31:1523-1531, 2003), dogs that were exsanguinated to cardiac arrest recovered fully, with normal functionality when flushed with normal saline at 2° C. to a tympanic temperature of 10° C. The dogs were resuscitated by closed-chest cardiopulmonary bypass, postcardiac arrest mild hypothermia (tympanic temperature 34° C.) to 12 hrs, controlled ventilation to 20 hrs, and intensive care to 72 hrs. Notably, two of the four dogs treated in this manner suffered moderate-to-severe overall disability ratings with less-than-normal neurological deficit scores.
Although reaching the two-hour mark for normal resuscitation is significant, it is not quite a workable time frame for many field injuries, especially battlefield injuries, which require transport by helicopter or other means, often from remote locations. This transport time, when added to the time required for patient evaluation and intervention, which can be complex in many trauma cases, uses up the two-hour resuscitation window quite rapidly. Therefore, a three or more-hour window is very much desired. In addition, an approach with more reliable intact neurological outcome for durations of less than three hours is also desirable.